1. Field of the Invention
The present disclosure relates to a method of cleaning showerhead; in particular, the present disclosure relates to method of cleaning showerhead for spraying manufacturing process gas by ultrasonic with a showerhead cleaning rack.
2. Description of Related Art
Integrated circuits usually are manufactured by the deposition processes and the etching processes. The deposition layer is deposited on a working piece. Next, the material of the deposition layer is etched to form a desired pattern. The above manufactured processes are implemented in a vacuum room.
Usually, the chemical reactants for the deposition or etching process includes one or more than one gas (referred to as the manufacturing process gas) and the manufacturing process gas is sprayed in the vacuum room by the showerhead located above the working piece. The manufacturing process gas is sprayed through the small holes located on the surface of the showerhead so as to form the desired manufacturing process gas disposition around the working piece.
When the deposition or etching process is finished, the showerhead needs to be cleaned so as to eliminate the pollutants in the showerhead. Thereby, when the deposition or etching process is performed again, the yield rate of the deposition or etching process will not be affected by the pollutants on the showerhead. Generally, when the showerhead is cleaned, the showerhead is placed in a clean trough that is fully filled with the cleaning agent, and an oscillation method is used to oscillate the cleaning agent so as to clean the pollutants on the showerhead. However, the cleaning method of the prior art cannot fully clean the pollutants. Therefore, the onsite engineer in the semiconductor factory must repeatedly clean the showerhead until the pollutants on the showerhead are fully removed. A lot of cleaning time and manpower are required, thus the production efficiency is affected.